[FIX] get_last_modified in case no file is provided
[FIX] get_last_modified in case no file is provided

akretion/openerp-web,havt/openerp-web,havt/openerp-web,havt/openerp-web,havt/openerp-web,havt/openerp-web,akretion/openerp-web,akretion/openerp-web